1.
Tech A says that the purpose of an anti-lock braking system is to prevent the wheels from locking during braking, especially on low-friction surfaces such as wet, icy, or snowy roads. Tech B says that the anti-lock braking system does not mean a vehicle can stop quickly on all road surfaces. Who is correct?
Correct Answer
C. Both Techs A and B
Explanation
Both Techs A and B are correct. Tech A is correct in stating that the purpose of an anti-lock braking system is to prevent the wheels from locking during braking, particularly on low-friction surfaces. This helps to maintain steering control and prevent skidding. Tech B is correct in stating that the anti-lock braking system does not guarantee that a vehicle can stop quickly on all road surfaces. Other factors such as road conditions, tire quality, and vehicle weight also play a role in stopping distance.
2.
The brake switch sends an electronic signal to which of the following?
Correct Answer
C. Both A and B
Explanation
When computer-controlled, the switch sends the signal to the control module to turn on the brake lights.
3.
Which of the following typically reports the vehicle's speed to the electronic brake control module?
Correct Answer
C. Both A and B
Explanation
The vehicle speed sensor and wheel speed sensor can be responsible for inputting vehicle speed to the electronic brake control module.
4.
Some anti-lock braking systems require a scan tool that connects to the electronic brake control module or power train control module to read the fault codes.
Correct Answer
A. True
Explanation
With ABS, most need a computer interface to access DTCs and other applicable data.
5.
Which of the following is a typical sensor used by the electronic stability control system?
Correct Answer
D. All of the above
Explanation
All of these sensors are used with electronic stability control.
6.
Some traction control systems can be temporarily deactivated by a traction control system function switch located on the dash or center console.
Correct Answer
A. True
Explanation
Most cars have a control button that can be used by the driver to disable traction control.
7.
Which of the following is used to diagnose an anti-lock braking system fault?
Correct Answer
C. Both A and B
Explanation
Both of these tools can be used in different applications to find various ABS related faults.
8.
Wheel speed sensors should be checked for which of the following with a DVOM?
Correct Answer
D. All of the above
Explanation
A WSS can be tested electrically for each of the above, with a DVOM.
9.
The tone wheel used on an anti-lock braking system's wheel speed sensors should be checked for which of the following?
Correct Answer
D. All of the above
Explanation
Missing or damaged teeth in the pulse wheel will trigger an ABS fault.
10.
On a vehicle with an electronic brake control module, if the yellow warning lamp is not illuminated and the brakes are not functioning properly, suspect a problem that is not monitored by the electronic brake control module.
Correct Answer
A. True
Explanation
The yellow/amber light is the color of light associated with ABS related faults.
11.
Which of the following modules executes the commands of the anti-lock braking system control module?
Correct Answer
C. Hydraulic control module
Explanation
The hydraulic control module is part of the ABS unit/system.
12.
Typical hydraulic control units for electronic brake control systems can have how many channels?
Correct Answer
D. All of the above
Explanation
Control units can have anywhere between 2 and 4 channels.
13.
If there is a fault with the hydraulic control unit, typically the unit is which of the following?
Correct Answer
B. Not serviceable in the field
Explanation
We typically do not service a hydraulic unit. It is most often replaced.
14.
Wheel speed sensors send electric signals to the electronic brake control module to determine the speed and rate of deceleration of each wheel.
Correct Answer
A. True
Explanation
Wheel speed sensors send a different frequency of pulse-based upon vehicle speed.
15.
Wheel sensor assemblies are comprised of a toothed tone wheel and a pick-up assembly, separated by a metal plate.
Correct Answer
B. False
Explanation
This is true other than the metal plate. That is not part of the assembly.
16.
Tech A says that all traction control systems apply the brakes as a first step and reduce engine power. Tech B says that some traction control systems do not apply the brakes as a first step but reduce engine power. Who is correct?
Correct Answer
B. Tech B
Explanation
Some traction control systems will reduce engine power by limiting the fuel injector open time.
17.
Tech A says that wheel speed senor operation can be tested with a DVOM. Tech B says that wheel speed senor operation can be checked with an oscilloscope. Who is correct?
Correct Answer
C. Both Techs A and B
Explanation
Both of these tools can be used to test a wheel speed sensor.
18.
Tech A says that if the yellow warning lamp is illuminated indicating a fault in the electronic brake control system, you should retrieve the diagnostic trouble codes and follow the procedure listed in the service information. Tech B says that if the yellow warning lamp is not illuminated and the brakes are not functioning properly on a vehicle with an electronic brake control system, you should suspect a problem that is not monitored by the electronic brake control module. Who is correct?
Correct Answer
C. Both Techs A and B
Explanation
Retrieving DTC's should be your first step when there is a yellow/amber ABS warning light. The light will also warn you that there is something wrong that is monitoring by the ABS control module/
19.
Which of the following is MOST likely to be in an electronic brake control module?
Correct Answer
D. All of the above
Explanation
All of the above are in the brake control module.
20.
Which of the following is LEAST likely to be an input to an electronic brake control module?
Correct Answer
A. Crank sensor
Explanation
The crank sensor is an input to the ECM and tells it the crank shaft's speed.
21.
Tech A says that bleeding an electronic brake control system is just like bleeding a non–electronic brake control system. Tech B says that if the air is allowed into the electronic brake control system, it can become trapped in the hydraulic control unit, requiring a scan tool to operate the solenoid valves to help bleed the air from the electronic brake control system. Who is correct?
Correct Answer
C. Both Techs A and B
Explanation
Bleeding on most vehicles with ABS is just like bleeding in non-ABS vehicles, but if air does become trapped in the module, a scan tool will be needed to open the valves and push the fluid through.
22.
Which brake fluid is LEAST likely to be used in an electronic brake control system?
Correct Answer
B. DOT 5
Explanation
DOT 5 fluid is not compatible with ABS modules.
23.
Tech A says that some anti-lock braking systems do away with the mechanical proportioning valve. Tech B says that the electronic brake control module performs an automatic self-check and warning lamp bulb check on the anti-lock braking system every time the key is turned to the “run” position. Who is correct?
Correct Answer
C. Both Techs A and B
Explanation
Self-testing is performed every time the vehicle is turned off, then on. The ABS module will act as a proportioning valve in late-model vehicles.
24.
All of the following are typical methods of reducing power in the vehicle when the electronic brake control module requests reduced power, EXCEPT:
Correct Answer
D. Selecting a lower gear in the transmission.
Explanation
The ABS module will not mess with the gearing of the transmission, but will do each of the others listed.
25.
Tech A says that a typical wheel speed sensor can be faulty due to a sensor resistance problem. Tech B says that a typical wheel speed sensor could be faulty due to no voltage supply. Who is correct?
Correct Answer
A. Tech A
Explanation
There can be excessive resistance in the sensor's windings. Wheel speed sensors create the voltage, they are not supplied it.
26.
Tech A says that in some cases, the electronic brake control module can be programmed with new tire size to restore proper electronic brake control performance. Tech B says that there could be an electronic brake control module available for installation that matches a new tire size. Who is correct?
Correct Answer
C. Both Techs A and B
Explanation
Some brake control modules can be programmed to the size of the vehicle's tires. Other applications may require replacing the module to match the module's programming to the installed tire size.